The proposed research would continue investigations now in progress under NIH Grant AM-11028-11A1. Continuing studies aim at inquiring into the pathogenesis of the lesions of the disease cystic fibrosis (CF). Current projects concern correlated cytochemical and biochemical studies of the sweat gland in culture with the primary purpose of differentiating the possible role of humoral CF factors vs. inherent structural or biochemical defects in a cell within the sweat gland. Cation fluxes are being investigated in sweat glands from normal and CF patient subjects maintained in culture in presence and absence of CF factors. Inquiry is also proceeding into pathogenetic mechanisms for development of abnormal megagranules in leukocytes, hepatocytes, renal tubules and other cells of beige mice with a disease analogous to the Chediak-Higashi syndrome of man. The contribution of accelerated autophagic processes related to increased plasmalemmal turnover to the development of some of the megagranules is under investigation. These studies also include attempts at culturing fibroblast lines from the beige mouse Chediak-Higashi model as a system for evaluating pathogenesis of the mega granules and factors influencing and modifying their development and as a means of investigating biochemical abnormalities in the plasma membrane or lysosomal granule membrane. Additional efforts are underway to develop new cytochemical procedures including adaptation of a modified Con A-peroxidase procedure to differentiation of mannose-rich complex carbohydrates in tissue sections as well as application of a peanut lectin peroxidase conjugate to localization of galactose-rich glycoproteins in sections and cell suspensions by light and electron microscopy. A tannic acid-uranyl acetate sequence for ultrastructural demonstration of complex carbohydrates is also under investigation. An immunostaining procedure for localizing carbonic anhydrase and its isozymes by light and electron microscopy is being developed and will be further compared with the cobalt-salt method for histochemical demonstration of carbonic anhydrase.